The Center's Laboratory Core is a collaborative effort of the University of Cincinnati and the Centers for Disease Control and Prevention, National Center for Environmental Health. All laboratory assays with the exception of pesticide samples taken in floor dust, will be done at these two sites. The core laboratory for the Children's Environmental Health Center will provide a central area for receipt of samples collected in the various projects and the distribution of the various sample types to the appropriate laboratories for analysis. Sample receipt, documentation and chain-of-custody will be maintained and all sample handling protocols carried out consistently across projects. This will protect sample integrity and ensure samples have been shipped, received and analyzed appropriately and under the quality assurance guidelines of the projects. The core laboratory will be associated with a non-profit facility within the University of Cincinnati called the Hematology and Environmental Laboratories. The main focus of the laboratory is the analysis of metals in a variety of biological and environmental matrices. This laboratory will be responsible for the analysis of all environmental samples for lead. The laboratory facilities consist of 8,947 square feet of space and include laboratory, offices, and instrument rooms. The laboratory is a reference lab for both the Wisconsin Occupational Health Laboratory and State of New York Blood Lead Proficiency Testing Programs. It is accredited by the American Industrial Hygiene Association as an Industrial Hygiene laboratory and also as an Environmental Lead Laboratory under the National Lead Laboratory Accreditation Program. The laboratory is certified by the State of New York Environmental Laboratory Accreditation Program and participates in the New York proficiency program for environmental sample analyses. Approval is also maintained in the State of Ohio for lead testing.